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3.3 Example of Empirical Distributions 37

values contained in the data vector are
max(corg)

ans =
14.5615
min(corg)

ans =
9.4168
The range of the data values, i.e., the difference between maximum and
minimum values is

range(corg)
ans =
5.1447

The range of the data is the information that we need in order to defi ne the
classes. Since we have decided to use eight classes, we split the range of the
data into eight equal-sized bins. The approximate width of the intervals is

5.1447/8

ans =
0.6431
We round this number up and defi ne

v = 10 : 0.65 : 14.55;
as midpoints of the histogram intervals. The commands for displaying the
histogram and calculating the frequency distribution are

hist(corg,v);
n = hist(corg,v);

The most important parameters describing the distribution are the averages
and the dispersion about the average. The most popular measure for average
is the arithmetic mean of our data.

mean(corg)
ans =
12.3448
Since this measure is very susceptible to outliers, we use the median as an